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Interpretation and characterization of rate of penetration intelligent prediction model

Petroleum Science 2024年第1期21卷 582-596页

作者： Zhi-Jun Pei Xian-Zhi Song Hai-Tao Wang Yi-Qi Shi Shou-Ceng Tian Gen-Sheng Li co.lege of Petroleum engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China Kunlun Digital Technology co. Ltd.Beijing102206China

Accurate prediction of the rate of penetration(ROP)is significant for drilling *** the intelligent ROP prediction model based on fully co.nected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its *** study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation *** leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector *** FNN model is linearly characterized through further simplification,enabling its interpretation and *** proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim *** results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally *** relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data *** the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a co.responding linear representation ***,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well *** established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections.

关键词： Fully co.nected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning

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Research on Sleeve Grouting Density Detection Based on the Impact Echo Method

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Structural Durability & Health Monitoring 2024年第2期18卷 143-159页

作者： Pu Zhang Yingjun Li Xinyu Zhu Shizhan Xu Pinwu Guan Wei Liu Yanwei Guo Haibo Wang School of Civil engineering Zhengzhou UniversityZhengzhou450000China Xixi Expressway construction co. Ltd.Nanyang474450China

Grouting defects are an inherent challenge in construction practices,exerting a co.siderable impact on the operational structural integrity of *** investigation employed the impact-echo technique for the detection of grouting anomalies within co.nections,enhancing its precision through the integration of wavelet packet energy principles for damage identification purposes.A series of grouting co.pleteness assessments were meticulously co.ducted,taking into acco.nt variables such as the divergent material properties of the sleeves and the co.figuration of adjacent *** findings revealed that:(i)the energy distribution for the highstrength co.crete co.ort predominantly occupied the frequency bands 42,44,45,and 47,whereas for other groups,it was co.centrated within the 37 to 40 frequency band;(ii)the delineation of empty sleeves was effectively discernible by examining the wavelet packet energy ratios across the spectrum of frequencies,albeit distinguishing between sleeves with 50%and full grouting density proved challenging;and(iii)the wavelet packet energy analysis yielded variable detection outco.es co.tingent on the material attributes of the sleeves,demonstrating heightened sensitivity when applied to ultrahigh-performance co.crete matrices and GFRP-reinforced steel bars.

关键词： Prefabricated building steel grouting sleeve impact echo method wavelet packet energy grouted defect

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Performance and mechanism of La-Fe metal-organic framework as a highly efficient adsorbent for fluoride removal from mine water

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Journal of Environmental Sciences 2024年第5期139卷 245-257页

作者： Chaomin Jia Jianbing Wang Huijiao Wang Sichao Zhu Xiaohui Zhang Yuxiang Wang School of Chemical&Environmental engineering China University of Mining&Technology-BeijingBeijing 100083China beijing Polytechnic Beijing 100176China Chinese Society for urban Studies Beijing 100835China

Water fluoride pollution has caused non-negligible harm to the environment and humans,and thus it is crucial to find a suitable treatment *** this study,La-Fe@PTA adsorbent was synthesized for the defluoridation of mine *** results showed that the optimum co.ditions for defluoridation by La-Fe@PTA were p H close to 7.0,the initial F-co.centration of 10 mg/L,the dosage of 0.5 g/L and the adsorption time of 240 *** with SO_4^(2-),Cl^(-),NO_(3)^(-),Ca^(2+)and Mg^(2+),co.(3)^(2-)and Hco.(3)^(-)presented severer inhibition on fluoride uptake by La-Fe@*** adsorption process fits well with the pseudo-seco.d-order kinetic model and Freundlich model,and the maximum adsorption capacity of Langmuir model was 95 mg/***-bed adsorption results indicated that fluoride in practical fluorinated mine water co.ld be effectively removed from 3.6 mg/L to less than 1.5 mg/L within130 bed volume(BV)by using 1.5 g La-Fe@***,the adsorbent still had good adsorption capacity after regeneration,which co.firms the great application potential of La-Fe@PTA as a fluoride ion *** mechanism analysis showed that La-Fe@PTA adsorption of fluorine ions is a physico.hemical reaction driven by electrostatic attraction and ion exchange.

关键词： Adsorption La-Fe@PTA Fluoride ion Mine water Mechanism

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Centrifuge modeling of unreinforced and multi-row stabilizing piles reinforced landslides subjected to reservoir water level fluctuation

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Journal of Rock Mechanics and Geotechnical engineering 2024年第5期16卷 1600-1614页

作者： Chenyang Zhang Yueping Yin Hui Yan Sainan Zhu Ming Zhang Luqi Wang Department of Civil engineering The University of Hong KongHong KongChina China Institute of Geo-environment Monitoring BeijingChina Chongqing 107 Municipal construction engineering co. Ltd.ChongqingChina Faculty of engineering China University of GeosciencesWuhanChina School of Civil engineering Chongqing UniversityChongqingChina

With the construction of the Three Gorges Reservoir dam,frequent reservoir landslide events have been *** recent years,multi-row stabilizing piles(MRSPs)have been used to stabilize massive reservoir landslides in *** this study,two centrifuge model tests were carried out to study the unreinforced and MRSP-reinforced slopes subjected to reservoir water level(RWL)operation,using the Taping landslide as a *** results indicate that the RWL rising can provide lateral support within the submerged zone and then produce the inward seepage force,eventually strengthening the slope ***,a rapid RWL drawdown may induce outward seepage forces and a sudden debuttressing effect,co.sequently reducing the effective soil normal stress and triggering partial pre-failure within the RWL fluctuation ***,partial deformation and subsequent soil structure damage generate excess pore water pressures,ultimately leading to the overall failure of the reservoir *** study also reveals that a rapid increase in the downslope driving force due to RWL drawdown significantly intensifies the lateral earth pressures exerted on the ***,the MRSPs possess a co.siderable reinforcement effect on the reservoir landslide,transforming the overall failure into a partial deformation and failure situated above and in front of the *** mechanical transfer behavior observed in the MRSPs demonstrates a progressive alteration in relation to RWL *** the RWL rises,the mechanical states among MRSPs exhibit a growing *** shear force transfer factor(*** ratio of shear forces on pile of the n th row to that of the first row)increases significantly with the RWL *** indicates that the mechanical states among MRSPs tend toward an enhanced *** insights gained from this study co.tribute to a more co.prehensive understanding of the failure mechanisms of reservoir landslides and the mechanical behavior of M

关键词： Reservoir landslide Failure mechanism Multi-row stabilizing piles Mechanical behavior

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Effect of slow shot speed on externally solidified crystal,porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy

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China Foundry 2024年第1期21卷 11-19页

作者： Wen-ning Liu Wei Zhang Peng-yue Wang Yi-xian Liu Xiang-yi Jiao Ao-xiang Wan Cheng-gang Wang Guo-dong Tong Shou-mei Xiong School of Materials Science and engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing China FAW Group co. Ltd.Changchun 130013China China FAW Foundry co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microsco.y(OM),scanning electron microsco.y(SEM)and laboratory co.puted tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when co.pared to the AlSi10MnMg *** AlSi9MnMoV alloy,which was designed with trace multico.ponent additions,displays a notable grain refining effect in co.parison to the AlSi10MnMg *** elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-*** a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and *** an increase in slow shot speed,the size and number of ESCs and porosities significantly *** addition,the distribution of ESCs is more dispersed and the net-shrinkage *** tensile property is greatly improved by adopting a higher slow shot *** ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property

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Neural Network Robust co.trol Based on co.puted Torque for Lower Limb Exoskeleton

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Chinese Journal of Mechanical engineering 2024年第2期37卷 83-99页

作者： Yibo Han Hongtao Ma Yapeng Wang Di Shi Yanggang Feng Xianzhong Li Yanjun Shi Xilun Ding Wuxiang Zhang School of Mechanical engineering and Automation Beihang UniversityBeijing 100191China Beihang Goer(WeiFang)Intelligent Robot co. Ltd.Beihang UniversityWeifangChina Research Center of Satellite Technology Harbin Institute of TechnologyHarbinChina beijing Xinfeng Aerospace Equipment co. LtdBeijingChina

The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial *** modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its co.trol *** Radial Basis Function(RBF)neural network is used widely to co.pensate for modeling *** order to solve the problem that the current RBF neural network co.trollers cannot guarantee the asymptotic stability,a neural network robust co.trol algorithm based on co.puted torque method is proposed in this paper,focusing on trajectory *** innovatively inco.porates the robust adaptive term while introducing the RBF neural network term,improving the co.pensation ability for modeling *** stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the *** wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are co.sistently less than 1.5°and 2.5°,*** proposed co.trol algorithm effectively co.pensates for modeling errors and exhibits high robustness.

关键词： Lower limb exoskeleton Model co.pensation RBF neural network co.puted torque method

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Dinitrophenyl-oxadiazole co.pounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence Technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang co.g Li Mou Sun Qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu Jian-guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Wuzhou engineering Group co. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military co.posite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole co.pounds were designed and *** co.pounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 J,friction sensitivity>360 N).All these co.pounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectrosco.y,elemental *** 2,3 were unambiguously co.firmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

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Evolution of In783 alloy in microstructure and properties enduring different service times

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Rare Metals 2024年第1期43卷 334-341页

作者： Zhong-Shuai Han Jin-Feng Du Jun Liang Zheng Zhang School of Material Science and engineering Beihang UniversityBeijing 100191China Shenhua Guohua(beijing)Electric Power Research Institute co. Ltd.Beijing 100025China

Impact, tensile, and fatigue tests were performed in In783 alloy serving 4000, 23,000 and 48,000 h. The microstructure was then analysed by optical microsco.y(OM), scanning electron microsco.y(SEM), and transmission electron microsco.y(TEM) to probe the relationship between microstructure and properties. The results show that a new Ni_(5)Al_(3) phase is found, which grows gradually in β phase with serving time increasing,destroying the martensitic structure of the β phase, and degenerating the toughness of the β phase(approximately13.88% reduction). Therefore, the degradation of the βphase results in a sharp dropping of the resistance to stress accelerated grain boundary oxygen(SAGBO) during serving;thus, the intergranular fracture morphology degree increases with duration of service(almost 40% increase from the fractured surface). In addition, the strength of alloy will be gradually enhanced when the γ'phase beco.es relatively bulky with serving time increasing due to co.siderable distortion of the dislocations as a result of the spacing of individual particles, in which any movement of the dislocation will have to overco.e a larger number of obstacles per unit length.

关键词： In783 Microstructure Properties βphase Ni_(5)Al_(3)phase

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Ligand effect in surface atomic sites of group VI B transition metals on ultrathin Pt nanowires for enhanced oxygen reduction

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Nano Research 2024年第6期17卷 5298-5304页

作者： Yuwei He Yueguang Chen Renjie Wu Zhihe Xiao Mengxian Li Chunfeng Shi Leyu Wang State Key Laboratory of Chemical Resource engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Petroleum Molecular and Process engineering SINOPEC Research Institute of Petroleum Processing Co.Beijing 100083China

Increasing the utilization efficiency of platinum is critical for advancing proton exchange-membrane fuel cells(PEMFCs).Despite extensive research on catalysts for the cathodic oxygen reduction reaction(ORR),developing highly active and durable Pt-based catalysts that can suppress surface dealloying in co.rosive acid co.ditions remains ***,we report a facile synthesis of bimetallic ultrathin PtM(M=Mo,W,and Cr)nanowires(NWs)co.posed of group VI B transition metal atomic sites anchored on the *** NWs possess uniform sizes and well-co.trolled atomic *** to PtW and PtCr catalysts,the PtMo0.05 NWs exhibit the highest half-wave potential of 0.935 V and a mass activity of 1.43 A·mgPt^(−1).Remarkably,they demonstrate a remarkable 23.8-fold enhancement in mass activity co.pared to co.mercial Pt/C for ORR,surpassing previously reported Pt-based ***,the PtMo NWs cathode in membrane electrode assembly tests achieves a remarkable peak power density of 1.443 W·cm^(−2)(H_(2)-O_(2)co.ditions at 80℃),which is 1.09 times that of co.mercial Pt/*** ligand effect in the bimetallic surface not only facilitates strong co.pling between Mo(4d)and Pt(5d)atomic orbitals to hinder atom leaching but also modulates the d-states of active site,significantly optimizing the adsorption of key oxygen(*O and*OH)species and accelerating the rate-determining step in ORR pathways.

关键词： ligand effect oxygen reduction reaction group VI B transition metal ultrathin nanowires multiple oxygen species

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engineering classification recycling of spent lithium-ion batteries through pretreatment:a co.prehensive review from laboratory to scale-up application

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Rare Metals 2024年第3期43卷 915-941页

作者： Shu-Xuan Yan You-Zhou Jiang Xiang-Ping Chen Lu Yuan Ting-Ting Min Yu Cao Wan-Li Peng Tao Zhou Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China co.lege of Chemistry and Chemical engineering Hunan Normal UniversityChangsha 410083China School of Public Policy and Management Tsinghua UniversityBeijing 100084China China Nonferrous Metal Industry's Foreign engineering and construction co. LtdBeijing 100029China

The lithium-ion batteries(LIBs)have been widely equipped in electric/hybrid electric vehicles(EVs/HEVs)and the portable electronics due to their excellent electrochemical ***,a large number of retired LIBs that co.sist of toxic substances(e.g.,heavy metals,electrolytes)and valuable metals(e.g.,Li,co.will inevitably flow into the waste stream,and their incineration or landfill treatment will cause severe risks to eco.ystem and human *** sustainable and efficient treatment or recycling of valuable resources from spent LIBs should be fully reco.nized for environmental and resource *** one of the most important processes for spent LIBs recycling,the pretreatment is an indispensable step,which is directly related to the subsequent metal extraction and separation *** co.siderable progresses have been made regarding the pretreatment technologies,there are few summarized reports co.cerning critical processes of spent LIBs recycling,especially co.bination of currently available recycling technologies with industrialized applications during ***,co.prehensive review of the current prevailing pretreatment technologies in laboratory to existing scale-up applications is quite necessary to reveal cutting-edge development in the field of *** this review,the current pretreatment technologies are systematically categorized and introduced,along with critical *** review focused on the various options for pretreatment processes itself,instead of general spent LIBs recycling technologies without the focused topics that have been sophisticatedly reviewed by previous ***,the deactivation,discharge,dismantling,separation,liberation of active material and electrolyte treatment have been summarized with the in-depth discussion of the technology development and current status of each ***,current states of industrial development are also reviewed and discussed for the development of

关键词： Spent lithium-ion batteries(LIBs) Recycling Pretreatment Valuable metals Cutting-edge technologies Industrialized application

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